Problem: Umaima was assigned pages 23 through 49 for homework tonight. If Umaima read all of the pages she was assigned, how many pages did she read?
Instead of counting pages 23 through 49, we can subtract 22 from each number so we instead consider pages 1 through 27. We see that Umaima read 27 pages. Notice that she read 27 and not 26 pages.